I have question regarding between-regions overlap in ROI analysis. I'm using MarsBar (with AAL structural roi's database), but i think anyone who conducted such analysis in the past might be able to contribute.
The problem arose when i saw a similar activity pattern between ROI'swithin the Inferior Frontal Gyrus in some of my contrasts (regions are:Orbitalis, Opercularis, Triangularis). This made me consider the possibility the the results aretwisted by an overlap between the regions, taking into account the SPM-Smoothing (FWMH: 7 7 7) i did in the pre-processing stage.
My concern is mainly about the Opercularis and the Triangularis which are quite adjacent (the Orbitalis is more easily separated).
Could you think of a way to calculate the measure of dependency between adjacent areas?